Myford ML7 backgear jammed

Yes. This sounds like the bronze sleeve carrying the pulley and smaller gear has fused onto the main shaft.

It's caused by doing a lot of backgear work and not lubricating regularly through the oil feed nipple on the side of the pulley.

The whole shaft will have to come out, but it's not that difficult a job. It's also a good idea to change the drive belt while you have it all in bits unless it's fairly new.

Loosen the securing ring which tightens up the shaft and compensates for endfloat. Remove the four cap screws holding the two bearings down. These will have shims underneath them, so please take great care not to lose them and to note where they came from (they will stick to the caps or the headstock).

The whole lot will then lift out and you can dismantle the shaft. A puller will be required to get it all apart. The shaft will need cleaning up to remove the bronze and generally this is all that will be required.

Stick it all back together with plenty of lubrication, set the endfloat, and you should be back in business.

Hello Duncan,

Thank you for your reply.

I was hoping that I wouldn't have to pull the spindle but if forcing WD40 into the oil nipple screw hole (after removing the nipple) does no good I pull the spindle on the weekend.

As there is some play in the headstock bearings ( at least in the larger of the two) I will also tighten these. I will seek profession help for that job as I understand the bearings are irreplaceable and as this would be my first bearing scraping I could easily destroy them.

Just to establish my amateur status - How does one remove bronze from the spindle after the gears and bearings etc have been removed?

regards ungifted amateur

Just one thing to add: on no account forget to put the new the new belt over the spindle before you reinstall it, torque up the bearings, set the endfloat, reinstall the gear on the end, screw on the chuck, refix the gear cover, refix the oilers. Don't ask, etc....

Even if you do free it off by this method, it will sieze up again fairly quickly. The only proper cure is to take it apart, clean the bronze off the steel shaft and if necessary clean up the inside of the sleeve with hand tools if there is evidence of galling. To be honest, it's not a particularly time consuming job.

There shouldn't be any need to scrape the bearings, they have removable shims to take up wear radially, and an adjustable ring to set the endfloat.

This is where the WD40 might be more useful, in conjunction with some wire wool to give the spindle a good clean. IIRC the spindle on the ML7 is not hardened so you have to take care with this (i.e. don't go mad with sandpaper etc.)

I've got Myford's manual which has some general guidance on assembly of the lathe, but I can't find any details of torque or endfloat settings. Are there some specs for these somewhere ?

-adrian

I seem to recall that Myford produces an A4 sized laminated instruction sheet specifically for doing this job. Why not give them a call on 0117 925 4222 - who better to ask? ( there's a feed line for somebody!)

--

Chris Edwards (in deepest Dorset) ..."There must be an easier way...!"

Thanks, I'll try them. I wonder why they don't put it in the manual ?

-adrian

Thank you to all who replied.

I now am much better informed as to the problem and it's probable solution.

regards ungifted amateur

Manual? - that's a laugh, I'm still waiting for the manual for the Super 7 Connoisseur I bought three years ago!

Sadly, I know from significant personal experience that Myford ain't the company it once was. If it weren't for their outstanding reputation and the reservoir of 'goodwill' they built up over 60 years, I suspect they would have long followed most of their contemporaries into oblivion. Watch this space!

I'll stop there before I say something libellous! --

Chris Edwards (in deepest Dorset) ..."There must be an easier way...!"